BACK (BTB and C-terminal Kelch) domain found in Drosophila melanogaster protein germ cell-less (GCL) and similar proteins
The GCL protein is a nuclear envelope protein highly conserved between the mammalian and Drosophila orthologs. Drosophila melanogaster GCL is a key regulator required for the specification of pole cells and primordial germ cell formation in Drosophila embryos. Both human germ cell-less protein-like 1 (GMCL1) and germ cell-less protein-like 1-like (GMCL1P1 or GMCL1L) may function in spermatogenesis. They may also be substrate-specific adaptors of an E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins.